1. Field of the Invention
The present invention refers to a device for discharging concrete, comprising a flexible hose, which is connected to a concrete supply line, preferably a concrete supply line of a concrete pump, said hose being provided with an input end which is associated with the supply line and through which the concrete conveyed through the supply line enters the hose and an output end through which the concrete conveyed through the hose leaves said hose for the purpose of discharge, said hose being adapted to be bent in at least one swivelling plane between a substantially straight initial position and a curved position, and further comprising a swivelling means for moving the hose from its straight initial position to its curved position, said swivelling means comprising at least one drawing and/or pushing means which is effective in the swivelling plane and which extends, at least at the initial position of the hose, outside of the longitudinal central axis of the hose and at least indirectly between a first bearing associated with the output end of the hose and fixedly connected to the hose and a second bearing associated with the input end and fixed relative to said input end at least in the drawing and/or pushing direction of the drawing and/or pushing means, and at least one actuating means being provided, which applies a drawing and/or pushing force to the drawing and/or pushing means and which is operatively connected to said drawing and/or pushing means in such a way that the distance between the first and second bearings can be reduced by actuating the respective actuating means, whereby the hose can be moved from its initial position to its curved position.
2. Description of the Related Art
Such a device is known e.g. from DE-A-2752605. This device is provided with a piston-cylinder unit by means of which the hose can be moved from its initial position to its curved position. Due to the fact that the output end can be swivelled relative to the input end, the concrete can be discharged such that it is applied to the areas aimed at without moving the concrete supply line itself. However, a device of this type proves to be disadvantageous insofar as the possible swivelling angle is strongly limited by construction-dependent circumstances. The swivelling angle is limited by the distance of the piston rod and of the piston-cylinder unit from the hose. For enlarging the swivelling angle, the distance between the piston-cylinder unit and the hose has to be enlarged. This, however, results in a substantial increase in the physical size and in the fact that a larger number of components is required so that the weight of the device will be increased; this is disadvantageous, especially in the case of long, projecting supporting arms. In addition, such a device does not suffice to fulfill all the requirements which have to be satisfied for operating a concrete pump.